Resume/ Abstract
Koucham M’hamed *1, Khalil Abdessamad 1,2, Soulaimani Saad, Ait khouia Yassine 2, EL Adnani Mariam 1
1Resources Valorization, Environment and Sustainable Development Research Team (RVESD), Department of Mines, Mines School of Rabat, Ave Hadj Ahmed Cherkaoui, BP 753, Agdal, Rabat 10090, Morocco;
2 Geology and Sustainable Mining Institute, Mohammed VI Polytechnic University, Lot 660, Hay Moulay Rachid, Ben Guerir 43150, Morocco
*Corresponding Author E-mail: mhamed.koucham@enim.ac.ma
Abstract. The sustainable management of mine tailings remains a pressing global challenge due to their potential environmental risks and substantial volumes. This study focuses on the copper tailings, assessing their environmental behavior and residual resource potential through a combination of advanced environmental testing and geostatistical modeling.
Environmental characterization was conducted using static tests, weathering cell experiments, and the Toxicity Characteristic Leaching Procedure (TCLP). The results demonstrated that the tailings are non-acid generating, with a pH range of 6.5 to 7.8, low sulfide oxidation rates, and minimal metal leachability. Key neutralizing minerals such as dolomite (27.4 wt.%) and calcite (2.4 wt.%) contribute to geochemical stability by buffering acidity and promoting the sequestration of metals in secondary mineral forms. The TCLP test confirmed the classification of the tailings as non-hazardous, indicating low risks of heavy metal mobilization under natural conditions. In parallel, geostatistical modeling using ordinary kriging provided a detailed estimation of residual copper resources within the tailings. Systematic sampling and analysis revealed an average copper grade of ~0.3%, with an estimated resource of 2,760 tonnes distributed across 3.73 million cubic meters (4.85 million tonnes) of tailings. The metallic content is predominantly associated with sulfide and carbonate minerals, exhibiting a low degree of liberation. This integrated approach underscores the dual potential of tailings for sustainable management and resource recovery. By combining rigorous environmental assessments with 3D geostatistical modeling, the study provides valuable insights for the re-mining and recycling of tailings as secondary raw materials, offering a pathway to reduce environmental risks while contributing to the circular economy in the mining sector.
Keywords: sustainable mine waste management, copper resource assessment, static and kinetic tests, Environmental and geochemical behavior assessment.